TextBox.TextChanged Event

Reference

Definition

Namespace:: System.Web.UI.MobileControls

Assembly:: System.Web.Mobile.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Occurs when the user changes the text of a TextBox. This API is obsolete. For information about how to develop ASP.NET mobile applications, see Mobile Apps & Sites with ASP.NET.

public:
 event EventHandler ^ TextChanged;

public event EventHandler TextChanged;

member this.TextChanged : EventHandler

Public Custom Event TextChanged As EventHandler

Event Type

EventHandler

Examples

The following example demonstrates how to use the TextChanged event to change the items in a SelectionList.

ASP.NET (C#)

<%@ Page Language="C#" 
    Inherits="System.Web.UI.MobileControls.MobilePage" %>
<%@ Register TagPrefix="mobile" 
    Namespace="System.Web.UI.MobileControls" 
    Assembly="System.Web.Mobile" %>

<script runat="server">
    void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            // Add items to the list
            SelectionList1.Items.Add(new 
                MobileListItem("Verify transactions","Done"));
            SelectionList1.Items.Add(new 
                MobileListItem("Check balance sheet","Scheduled"));
            SelectionList1.Items.Add(new
                MobileListItem("Call customer", "Done"));
            SelectionList1.Items.Add(new
                MobileListItem("Send checks", "Pending"));
            SelectionList1.Items.Add(new
                MobileListItem("Send report", "Pending"));
            SelectionList1.Items.Add(new
                MobileListItem("Attend meeting", "Scheduled"));

            // Show all items in list
            SelectionList1.Rows = SelectionList1.Items.Count;
        }
    }
    void TextChanged(object sender, EventArgs e)
    {
        // Called during PostBack, if changed
        string task = TextBox1.Text;
        string status = TextBox2.Text;
        
        if (task.Length > 0 && status.Length > 0)
        {

            MobileListItem li = new MobileListItem(task, status);
            
            // Remove the item if it exists
            if (SelectionList1.Items.Contains(li))
                SelectionList1.Items.Remove(li);
            else
                // Add the item if it does not exist
                SelectionList1.Items.Add(li);

            // Clear the text boxes
            TextBox1.Text = String.Empty;
            TextBox2.Text = String.Empty;
        }

        // Display all items.
        SelectionList1.Rows = SelectionList1.Items.Count;
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<body>
    <mobile:Form id="Form1" runat="server">
        <mobile:Label Id="Label1" runat="server">
            Create a new Task with Status</mobile:Label>   
        <mobile:SelectionList runat="server" BreakAfter="true" 
            SelectType="ListBox"
            id="SelectionList1" />
        <mobile:Label Id="Label2" runat="server" 
            Text="Enter the Task name" />
        <mobile:TextBox runat="server" id="TextBox1" 
            OnTextChanged="TextChanged" />
        <mobile:Label Id="Label3" runat="server" 
            Text="Enter the Task status" />
        <mobile:TextBox runat="server" id="TextBox2" />
        <mobile:Command ID="Command1" runat="server" 
            Text="Submit" />
    </mobile:Form>
</body>
</html>

<%@ Page Language="VB" 
    Inherits="System.Web.UI.MobileControls.MobilePage" %>
<%@ Register TagPrefix="mobile" 
    Namespace="System.Web.UI.MobileControls" 
    Assembly="System.Web.Mobile" %>

<script runat="server">
    Protected Sub Page_Load(ByVal byvalsender As Object, _
        ByVal e As EventArgs)

        If Not IsPostBack Then
            ' Add items to the list
            SelectionList1.Items.Add(New _
                MobileListItem("Verify transactions", "Done"))
            SelectionList1.Items.Add(New _
                MobileListItem("Check balance sheet", "Scheduled"))
            SelectionList1.Items.Add(New _
                MobileListItem("Call customer", "Done"))
            SelectionList1.Items.Add(New _
                MobileListItem("Send checks", "Pending"))
            SelectionList1.Items.Add(New _
                MobileListItem("Send report", "Pending"))
            SelectionList1.Items.Add(New _
                MobileListItem("Attend meeting", "Scheduled"))

            ' Show all items in list
            SelectionList1.Rows = SelectionList1.Items.Count
        End If
    End Sub
    
    Private Sub TextChanged(ByVal sender As Object, _
        ByVal e As EventArgs)

        ' Called during PostBack, if changed
        Dim task As String = TextBox1.Text
        Dim status As String = TextBox2.Text
        
        If (task.Length > 0 AndAlso status.Length > 0) Then
            Dim li As New MobileListItem(task, status)

            ' Remove the item if it exists
            If (SelectionList1.Items.Contains(li)) Then
                SelectionList1.Items.Remove(li)
            Else
                ' Add the item if it does not exist
                SelectionList1.Items.Add(li)
            End If

            ' Clear the text boxes
            TextBox1.Text = String.Empty
            TextBox2.Text = String.Empty
        End If

        ' Display all items.
        SelectionList1.Rows = SelectionList1.Items.Count
    End Sub
</script>

<html xmlns="http:'www.w3.org/1999/xhtml" >
<body>
    <mobile:Form id="Form1" runat="server">
        <mobile:Label Id="Label1" runat="server">
            Create a new Task with Status</mobile:Label>   
        <mobile:SelectionList runat="server" 
            SelectType="ListBox"
            id="SelectionList1" />
        <mobile:Label Id="Label2" runat="server" 
            Text="Enter the Task name" />
        <mobile:TextBox runat="server" id="TextBox1" 
            OnTextChanged="TextChanged" />
        <mobile:Label Id="Label3" runat="server" 
            Text="Enter the Task status" />
        <mobile:TextBox runat="server" id="TextBox2" />
        <mobile:Command ID="Command1" runat="server" 
            Text="Submit" />
    </mobile:Form>
</body>
</html>

Remarks

When the user changes the text of a TextBox, this event is not raised immediately. The form must contain a Command to initiate a postback event that raises the TextChanged event.

Applies to

Product	Versions
.NET Framework	1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

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